5/28/85 OR 4,519,676
United States Patent m
teVelde
[l l] Patent Number: [45] Date of Patent:
[54] PASSIVE DISPLAY DEVICE
[75] Inventor: Ties S. te Velde, Eindhoven, Netherlands
[73] Assignee: U.S. Philips Corporation, New York, N.Y.
[21] Appl. No.: 460,420
[22] Filed: Jan. 24, 1983
[30] Foreign Application Priority Data
Feb. 1, 1982 [NL] Netherlands 8200354
[51] Int. CI.*. G02D 25/00
[52] U.S. CI. .. 350/269; 350/486;
340/763;340/783
[58] Field of Search 156/664; 350/486, 267,
350/269, 360; 340/763, 764, 783, 787, 788,
815.04
[56] References Cited
U.S. PATENT DOCUMENTS
Re. 31,498 1/1984 te Velde 350/486
4,178,077 12/1979 te Velde 350/486
4,309,242 1/1982 te Velde 156/644
Primary Examiner—Bruce Y. Arnold
Assistant Examiner—William Propp
Attorney, Agent, or Firm—Paul R. Miller
[57] ABSTRACT
On the facing surfaces of first and second supporting plates, where at least the first supporting plate is transparent, first and second electrodes, respectively, are provided with at least the first electrodes being transparent. An opaque liquid is present between the supporting plates. Third electrodes which can be moved between the first and second electrodes by electrostatic forces are connected to the second supporting plate. The third electrodes are formed by a display part having a large number of apertures of which the color of the side facing the first supporting plates is contrasted with the color of the liquid. A number of resilient elements is provided below the display part with one end connected to the display part and the other ends connected to pillars which are provided on the second supporting plate.
18 Claims, 19 Drawing Figures
